const test = require('node:test')
const assert = require('node:assert')
const { expandEvents, computeAtRisk, LOOKAHEAD_DAYS } = require('../src/atRisk')

const TODAY = new Date(2026, 7, 15) // 2026-08-15

// 距今 10 天的公历纪念日，提前 3 天提醒
const near = {
  id: 'a1', personName: '张三', remindEnabled: 1, importance: 'high',
  isLunar: false, solarMonth: 8, solarDay: 25, remindDays: 3
}
// 距今 40 天
const mid = {
  id: 'a2', personName: '李四', remindEnabled: 1, importance: 'low',
  isLunar: false, solarMonth: 9, solarDay: 24, remindDays: 7
}

test('LOOKAHEAD_DAYS 为 60', () => {
  assert.strictEqual(LOOKAHEAD_DAYS, 60)
})

test('一条纪念日展开出「当天」和「提前」两个事件', () => {
  const events = expandEvents(near, TODAY)
  assert.strictEqual(events.length, 2)
  const onDay = events.find(e => e.kind === 'onDay')
  const ahead = events.find(e => e.kind === 'ahead')
  assert.strictEqual(onDay.fireInDays, 10)
  assert.strictEqual(ahead.fireInDays, 7)
})

test('remindDays 为 0 时只有当天事件', () => {
  const events = expandEvents({ ...near, remindDays: 0 }, TODAY)
  assert.strictEqual(events.length, 1)
  assert.strictEqual(events[0].kind, 'onDay')
})

test('超出 60 天窗口的事件被过滤掉', () => {
  const far = { ...near, solarMonth: 12, solarDay: 25, remindDays: 3 }
  assert.strictEqual(expandEvents(far, TODAY).length, 0)
})

test('提前日已过、当天未到时，只剩当天事件', () => {
  // 距今 2 天，但提前 7 天的时点早已过去
  const soon = { ...near, solarMonth: 8, solarDay: 17, remindDays: 7 }
  const events = expandEvents(soon, TODAY)
  assert.strictEqual(events.length, 1)
  assert.strictEqual(events[0].kind, 'onDay')
})

test('余额足够时没有风险', () => {
  const r = computeAtRisk([near, mid], 10, TODAY)
  assert.strictEqual(r.atRiskCount, 0)
  assert.deepStrictEqual(r.atRiskNames, [])
})

test('余额为 0 时全部有风险', () => {
  const r = computeAtRisk([near, mid], 0, TODAY)
  assert.strictEqual(r.atRiskCount, 4)
  assert.deepStrictEqual(r.atRiskNames, ['张三', '李四'])
})

test('按时间先后消耗额度，后面的才有风险', () => {
  // 张三的两个事件在第 7、10 天，李四的在第 33、40 天
  const r = computeAtRisk([near, mid], 2, TODAY)
  assert.strictEqual(r.atRiskCount, 2)
  assert.deepStrictEqual(r.atRiskNames, ['李四'])
})

test('人名去重，同一人占两条只出现一次', () => {
  const r = computeAtRisk([near], 0, TODAY)
  assert.strictEqual(r.atRiskCount, 2)
  assert.deepStrictEqual(r.atRiskNames, ['张三'])
})

test('未开启提醒的纪念日不参与计算', () => {
  const r = computeAtRisk([{ ...near, remindEnabled: 0 }], 0, TODAY)
  assert.strictEqual(r.atRiskCount, 0)
})